Thread brake, in particular for double twisting spindles



Jan. 19; 1965 KREUSCHMER THREAD BRAKE, IN PARTICULAR FOR DOUBLE TWISTING SPINDLES 2 Sheets-Sheet 1 Filed May 29, 1963 INVENTOR. RUDOLF KREUSCHMER BY M W ATTORNEYS Jan. 19, 1965 R. KREUSCHMER 3,165,882

THREAD BRAKE, IN PARTICULAR FOR DOUBLE TWISTING SPINDLES Filed May 29, 1963 2 Sheets-Sheet 2 inf-=2 INVENTOR. RUDOLF KREUSCHMER flM/i; Wan

ATTORNEYS United States Patent 3,165,882 TIREAE) BRAKE, IN PARTICULAR FUR DQUBLE TWTSTENG SPINDLES Rudolf Kreusehmer, Kottern-Neudorf, Germany, assignor to Allma Allgauer Maschinenbau G.rn.h.H., Kenrpten,

Allgau, Germany Filed IVIHY 29, 3563, Ser. No. 284,132

11 Claims. (ill. 57-5883) This invention relates to a thread brake, in particular for double twisting spindles with non-rotating spools, in which the thread removed from the spool by the take-off flyer is guided over a brake cylinder rotating with a thread guide head, and the braking action is controlled in accordance with the tension of the thread by varying the angle through which the thread is wrapped around the brake cylinder.

Several constructions are known which, with the spool full, can be so adjusted that there is a definite wrapping angle of the thread on the storage disc at the commencement of the twisting operation. As the spool reduces, the tension of the thread between the spool and the brake increases so that the angle of wrapping on the storage disc would become smaller if the action of the brake were not reduced as the spool decreases. In the known constructions the reduction in the braking effect in accordance with the thread tension takes place in a plurality of stages corresponding to rest positions of the brake, or continuously by overcoming a frictional force. A particular disadvantage of this however is that during the twisting operation peaks of tension occur giving rise to an unintended displacement of the brake and hence a reduction in the braking effort to which the brake has been adjusted. There is a further considerable disadvantage in that the variations in thread tension caused by the running of thread from the spool, due to the thread being taken from the upper part of the spool under low tension and from the lower part under higher tension, give rise to displacement of the brake only to its maximum value if this is so large that the force necessary to displace the brake is present.

The object of the invention is to overcome the above mentioned disadvantages. This is effected, in a thread brake of the type mentioned initially, by providing on the thread guide head two thread guides which are relatively rotatable about the spindle axis against spring action, the first thread guide leading the thread coming from the spool to the brake cylinder while the other thread guide leads the thread running tangentially from the brake cylinder to the entry opening of the hollow spindle of the spool. With this new construction there is obtained a thread brake which operates satisfactorily and is self regulating. With increasing thread tension relative rotation of the two thread guides reduces the angle of wrapping around the brake cylinder so that the increased initial thread tension is compensated.

Embodiments of the invention are shown by way of example in the accompanying drawings in which:

FIG. 1 is a perspecitve and diagrammatic view of a thread brake according to the invention,

FIG. 2 shows a modification of the thread brake according to FIG. 1,

FIG. 3 is a vertical section through a preferred form of thread brake, and

FIG. 4 is a plan view of the thread brake shown in FIG. 3.

In FIG. 1 reference numeral 1 indicates the spool of a double twisting frame, reference numeral 2 indicates the hollow spindle of this spool and reference numeral 3 indicates a thread guide head which has a brake cylinder 4 and which rotates around the hollow spindle as thread is withdrawn. The thread removed from the spool ice 1 by the take-off flyer 5 is guided around the brake cylinder in the direction shown by the arrow, the thread tension being adjusted by variation of the wrapping angle. For this purpose there are arranged on the thread guide head two thread guides 8 and 9 which are rotatable around the axis 6 of the spindle against the action of a spring '7, the first thread guide 8 leading the thread Illa coming from thes pool to the brake cylinder 4, while the second thread guide 9 leads the thread 10b running tangentially olf the brake cylinder to the entry opening 11 of the hollow spindle 2 of the spool. The thread guide 9 is fixedly mounted on the thread guide head 3, as is also the part 12 to which the spring 7 is fixed. In contrast, the thread guide 5, 8 is rotatably mounted on the spindle 2 or the thread guide head 3. Upon the occurrence of peaks of tension or increased thread tension in the thread 10a being removed from the spool the thread guide 8 is moved against the action of the spring 7 in the direction of arrow A relative to the spindle head 3 so that the angle of wrapping of the thread around the brake cylinder 4 is reduced and the increased initial thread tension is thereby compensated, so that the tension in the running off thread 1611 is maintained substantially constant. In the modified construction shown in FIG. 2 the thread guide 8 is preceded by the take-off flyer 13 which is fixedly mounted on the thread guide head 3. The arrangement of the other parts is the same as in FIG. 1, so that with increased tension in the part 16a of the thread the thread guide 5, 8 is rotated rela tive to the thread guide head against the action of spring '7 and the angle of Wrapping around the brake cylinder 4 is reduced.

In the construction illustrated in FIGS. 3 and 4, the thread guide head consists essentially of the take-off carrier 14 formed integrally with the brake cylinder 4, a cap 15a, 15b carrying the second thread guide 9 and a helical spring 16 arranged within this cap and connecting together the two thread guide carriers which are mounted so as to be rotatable around the spindle ans 6. As can be seen from the drawing the cap consists of two parts, namely the hollow core 15b that serves to locate the cap on the spindle extension 2a and contains the helical spring 16, and the outer cap 15a which is releasably connected to this core. The outer cap 15a is forced onto the core 15b which is of slightly conical form at 17 and is secured against rotation by a radially arranged pin 18 or the like which engages in a recess 19 in the cap 15a. The helical spring 16 is connected at one end 16a to the hollow core 15b and at its other end lab to the take-.oif carrier 14. The latter, or the thread guide 8, can therefore rotate relative to the thread guide 9 or the cap 15a, 15b against the force of the spring 16. This rotary movement is limited by the two stop pins 20 and 21 which are arranged on the brake cylinder 4 and the core 15b respectively.

The thread guides 5, 8 and a and the perforated disc 22 that likewise serves to guide the thread are so arranged that they can be conveniently mounted on the thread guide head or exchanged. For this purpose the carrier 14 is formed as a flange on the periphery of which is provided a groove 23 with a radial bore 24. In this groove engages the arcuate part 5a of the take-off flyer 5 which has a radially bent end 5b which engages in the bore 24 and thus secures the take-01f flyer 5 to the carrier 14 non-rotatably.

The thread guide 9 is similarly formed and mounted, also having an arcuate locating portion 25 located with a press fit in a corresponding groove 26 on the periphery of the cap 15a. The thread guide 9 can thus be adjusted in the circumferential direction relative to the cap 15:: against the force due to the press fit. By this adjustment the angle of wrapping around the brake cylinder 4 grease-2 J andthus the thread tension can be adjusted. There is advantageously provided on the periphery of the cap 15:: a numbered scale or the like 27 for showing the position of the thread guide 9.

As. can be seen from the drawing the outer cap 35a tapers conically upwards and is so constructed that the thread runs freely from/the second thread guide 9 to the perforated disc 22. There is preferably provided on the cap 15a an exchangeable perforated disc, in which case the disc 22 may have a short hollow spigot 22a that can be press fitted into a corresponding aperture in the cap 15a.

The whole of the thread guide head described is rotatably mounted on the stationary hollow spindle 2 or its extension 2a. For this purpose a needle bearing is provided at 28 and a thrust bearing at 29, on which the thread guide carrier 14 and brake cylinder 4 are mounted. FIG. 4 shows the guiding of the thread that occurs in the operation of the thread guide head of FIG. 3. The thread 100 removed from the spool is guided via the eye 8 of the take-off flyer to the brake cylinder 4. The thread runs over the brake cylinder 4 with a wrapping angle a which may be smaller or larger than 360. The thread ltlb running tangentially Off this cylinder is then guided via the second thread guide 9 to the perforated disc 22, and thence to the entry opening 11 of the hollow spindle.

When the thread is drawn through the hollow spindle 2 the take-off fiyer 5, 8 is moved around the spindle axis in the direction B. With increased tension in the part a of the thread there is an opposing force such that the wrapping angle :1 around the brake cylinder 4 and thus the eiiect of the brake is reduced. Variations in tension are therefore automatically adjusted and the thread tension in the running off part 10b is kept substantially constant.

I claim:

1. A rotatable thread guide and thread brake head,

especially for double twisting spindles, comprising:

a hollow spindle;

a take-off carrier mounted on said spindle;

a take-0H flyer mounted on said carrier, said take-oil flyer including a first thread guide;

a brake cylinder projecting from said carrier;

a cap mounted for rotation with respect to said carrier;

a second thread guide mounted on said cap for rotation therewith with respect to said first thread guide;

a torsion coil spring arranged within said cap and concentric with. said spindle and connected to said cap and said carrier for yieldably restraining relative rotation therebetween whereby when the tension of a thread engaging said thread guides increases, said cap and said take-off carrier rotate relatively to each other against the spring pressure to decrease the angle through which the thread is wrapped around said brake cylinder.

2. A rotatable thread guide and thread brake head according to claim 1, including a tubular extension of said hollow spindle on which said cap is rotatably mounted, said brake cylinder being afiixed to said extension, and roller bearing means rotatably supporting said extension on said spindle.

3. A rotatable thread guide and thread brake head according to claim 1 wherein the take-off carrier has a fiange on the periphery of which there is formed a groove with a radial bore and the take-off flyer has an arcuate part which is located in the groove, said arcuate part having a radially bent end extending into said radial bore to secure the take-oft" flyer against rotation with respect to said carrier.

4. A rotatable thread guide and thread brake head according to claim 1 wherein said second thread guide is arranged on said cap so as to be adjustable in the circumferential direction.

5. A rotatable thread guide and thread brake head according to claim 1 wherein the second thread guide has an arcuate locating part, said cap having a groove in its periphery, said arcuate locating part being pressfitted into said groove.

6. A rotatable thread guide and thread brake head according to claim 1 wherein a replaceable perforated disc is provided at the upper end of the cap for guiding the thread.

7. A rotatable thread guide and thread brake head according to claim 6 wherein the perforated disc has a short hollow boss which is fitted with a press fit in a corresponding bore in said cap.

8. A rotatable thread guide and thread brake head according to claim 6 wherein the cap, tapers conically in an upward direction and is so constructed that the thread can run freely from said second thread guide to said perforated disc.

9. A rotatable thread guide and thread brake head according to claim 1 wherein the cap consists of a hollow core that serves to position said cap on said hollow spindle and contains said torsion coil spring, and an outer cap releasably connected to said core.

10. A rotatable thread guide and thread brake head according to claim 9 wherein said core is slightly conical and said outer cap is press fitted onto said slightly conical core and is secured against rotation. with respect thereto.

11. A rotatable thread guide and thread brake head according to claim 9, including stops for limiting the relative rotational movement between said brake cylinder and saidcore.

References (liter! in the file of this patent UNITED STATES PATENTS 787,717 Bates Apr. 18, 1905 1,495,024 Lipps May 20, 1924 2,397,153 Naumann Mar. 26, 1946 FOREIGN PATENTS 640,112 Canada Apr. 24, 1962 1,091,466 Germany Oct. 20, 1960 1,100,520 Germany Feb. 23, 1961 411,423 Italy Aug. 7, 1945 

1. A ROTATABLE THREAD GUIDE AND THREAD BRAKE HEAD, ESPECIALLY FOR DOUBLE TWISTING SPINDLES, COMPRISING: A HOLLOW SPINDLE; A TAKE-OFF CARRIER MOUNTED ON SAID SPINDLE; A TAKE-OFF MOUNTED ON SAID CARRIER, SAID TAKE-OFF FLYER INCLUDING A FIRST THREAD GUIDE; A BRAKE CYLINDER PROJECTING FROM SAID CARRIER; A CAP MOUNTED FOR ROTATION WITH RESPECT TO SAID CARRIER; A SECOND THREAD GUIDE MOUNTED ON SAID CAP FOR ROTATION THEREWITH WITH RESPECT TO SAID FIRST THREAD GUIDE; A TORSION COIL SPRING ARRANGED WITHIN SAID CAP AND CONCENTRIC WITH SAID SPINDLE AND CONNECTED TO SAID CAP AND SAID CARRIER FOR YIELDABLY RESTRAINING RELATIVE ROTATION THEREBETWEEN WHEREBY WHEN THE TENSION OF A THREAD ENGAGING SAID THREAD GUIDES INCREASES, SAID CAP AND SAID TAKE-OFF CARRIER ROTATE ELATIVELY TO EACH OTHER AGAINST THE SPRING PRESSURE TO DECREASE THE ANGLE THROUGH WHICH THE THREAD IS WRAPPED AROUND SAID BRAKE CYLINDER. 